Various filters have been employed to remove at least some impurities from water or wastewater. Prior filters include but are not limited to upflow filters or upflow clarifiers, downflow filters or downflow clarifiers, bi-flow filters and aerators. Preferred forms of the present invention are directed to a filter of any suitable type and/or an air scour system operably associated therewith to enhance one or more of numerous aspects of the filtration process including: (i) installation of the filter and/or various components thereof; (ii) servicing of the filter and/or components thereof; and/or, (iii) operation of the filter during a filtration cycle and a cleaning cycle.
Preferred forms of the present invention are further directed to air grids for aerating wastewater in an aerator tank for wastewater.
Preferred forms of the present invention further include a tool for inserting a drop pipe and one or more components attached to the drop pipe in a filter compartment. The tool can also be configured to remove the drop pipe and one or more components attached to the drop pipe from the filter compartment.
By way of example only and not limitation, filters having granular beds have employed air scour devices to improve cleaning of the granular filter bed. U.S. Pat. Nos. 5,534,202 and 5,673,481 disclose, inter alia, a known air scour system and a method of installing the same.